Switch mechanism



Feb. 16 1926.

H. K. KRANTZ SWITCH MECHANISM Filed April 18, 1922 3 Sheets-Sheet 1 IFIVENTOR Huber) K. Kranl? ATTORNEY WITNESSES:

H. K. KRANTZ SWITCH MECHANISM s Sheets-Shet 2 Filed April 18, 1922 A INVENTOR /7uberf/(.Krani2 ATTORNEY Feb. 16 1926.

HQ: WITNESSES: 'ikma,

Feb. 16,1926. 1,572,938

H. K. KRANTZ SWITCH MECHANISM Filed April 18. 1922 3 Sheets-Sheet 5 WITNESSES: INVENTOR Patented Feb. 15, 1926.

iJNlTED STATES PATENT OFFICE.

HUBER-T K. KRANTZ, OF \VILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC & MANUFACTURING CGHPANY, A CORPORATION OF PENNSYL- VANIA.

SWITCH 1VIEGHANISM.

Application filed April 18, 1922.

To alluhom it o'na concern Be it'kn'own that I, Hnnnn'r K. :KRANTZ, a citizen of the United States, and a resident of \Vilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Switch Mechanism, of which the following is a specification.

My invention relates to switch mechanism and particularly to switch mechanism of the safety enclosed type.

One object of my invention is to provide a simple positive interlocking mechanism between the door for the housing and the switch wherein predetermined movement of the switch and door are prevented by an interlocking member, and wherein the movement of the interlocking member is prevented except when the door and switch are in predetermined positions.

Another object of my invention is to provide a switch mechanism, having the above characteristics, wherein a latch mechanism serves to hold the door closed both at its free and atits hinged edges.

Another object of my invention is to provide an interlock mechanism for a safety switch wherein the interlocking bar is actuated by the latch for the door and wherein the switch is locked in open position by the latch before any opening'movement of the door is permitted.

Another object of my invention is to provide an interlock mechanism of the abovedesignated character, wherein the interlocking bar is locked in switch-retaining position by the cover when the latter is out of any position other than closed position.

Another object of my invention is to provide a switch mechanism wherein the interlocking bar is slidably secured to the housing and wherein the operating incchain ism therefor iscarried by the movable cove r. A further object of my. invention is to provide a switch interlock and door mechanism that is particularly well adapted for use with rotary switches having a snap action, such as switches of the type illustrated and described in the co-pcnding application Serial No. 420,047, filed October 27, 1920, by O. S. Jennings, and assigned to the Westinghouse Electric & Mfg. Companyf These and other objects, that will be made apparent throughout the further description of my invention, may be attained Serial No. 555,140.

by means of the switch mechanism hereinafter described, and illustrated in the accompanying drawings, wherein:

Figure 1 is a front view of the switch mechanism, a portion of the cover being broken away to expose parts of the switchinterlock mechanism;

Fig. 2 is an elevational view of the switch mechanism illustrated in Fig. 1, showing a portion of the side of the cover and operating mechanism broken away;

Fig. 3 is a transverse section through the switch mechanism taken on the broken line II.IIII of Fig. 2, looking in the direction of the arrows;

Fig. 42 is a transverse section on the broken line IV-IV of Fig. 1, looking in the direction of the arrows;

Fig. 5 illustrates front, side and end clevations of a detail of the door latch mechanism;

Figs. 6 and 7 are front and end views, respectively, of a detail of the switch-inte"- lock mechanism;

Figs. 8 and 9 are front and end views, respectively, of a detail of the door-latch mechanism; and

Figs. 10 and 11 are front and end views, respectively, of the interlocking bar.

Referring to the drawings, the apparatus includes a rectangular housing 12 that is made of sheet metal. The housing is providcd with a sheet-metal cover 13 having a marginal strip 14: that fits over the side and end walls of the housing. provided with an arcuate portion 15 extending above the plane of the cover for the purpose of providing a space within which switch-blade members may operate when moved to open position. The cover is also provided. with an opening 16 through which the usual fuse devices oi the switch apparatus are accessible. This opening is closed by a movable door 17 that is secured thereto by means of hinges 18.

The main cover 13 is pivoted to the housing 12 by means of hinges 19 and is adapted to be locked in closed position by means of a pair of clips 21 and 22, the former being secured to the housing 12, while the latter is an integral part of a handle plate 23 that is secured to the side wall of the cover 13. The clips 21 and 22 are severally provided witl'r perforations 21 that are aligned when the cover is in closed position and through The cover is Lit) which the hasp of a locl: may he inserted for locking the cover in closed position.

The handle plate 23 provided wi h an openin through which the fingers ot the operator may be insert d tor operatin the cover, and a spring clip riveted to the plate and provided with a yielding projecting end 27 that is adapted to snap into notch 28 in a plate 29 that is secured to the housing and. which extends slightly he yond the edge thereof. The latch, comprising the clip 27 and the slot 28, serves to yicldingly retain the cover in closed position.

A. switch panel of standard construction is mounted in the housing and compriz s an insulating panel 31 upon which mounted tuse clius EL. switch contact members :53 and switch pivot-jaw members list. A movable switch blade is mounted in each of the switch pivot-jaw. members 34, there heing three in the switch mechanism illustrated herein. Each switch-blade memher provided with an insulating plate SOhaving a notch into which the switch-operating arm 38 is inserted.

The switch arm 38 is of standard construction consisting of a piece of round commercial bar bent to provide bearing portions 39 and 40 thatare journallcd in the side walls of the housing. The end 4-.0. projects from the housing and attached to a switch-operating mechanism 41 which may he of any preferred form, such, for instance, as that disclosed in the above-mentioned co-pending' application.

A cam plate 4-2 is secured to the bar 38 hy means of screws. 4.3 and is moved with the switch. The cam consists of a flat metallic plate having its edge curved concentric with the axis of rotation of the switch arm. One end. of the plate terminates adjacent the arcuate surface in a projecting finger 44, the purpose (it which will hereinatter appear. 7

An interlocking bar 45, which YODSlbtS of a 'tiat metal. plate bent. in the shape of an angle har, is slidahly mounted upon the und rle of the cover 13 and is secured thereto by means of rivets 46 that project through slots 47 in the interlocking bar Tl'ie door 1'? provided with. an inwardlyproj s ir cam plate (see Figs. 1, 3 and a curved edge it) concentric with or hinges 123. One end 50 of the i p rtion of the plate termim tanco it nu the inner. surface or the The flange a: of the interlocking bar projects between the end of the plate 8 and the door 1?. So long: as the interlocking hgir =55 in the position illustrated in F 1 nd at, opening movement of the door i pr "enter. by reasonof. e; nnent ot' the oar 4Z5 withthe plate s8. 3

seen. t, when the interlockit will he ing bar 15 is in the open position shown in Fig. 1, the right end thereof clears the cam ite and permits opening and closing ven'ient ot the switch. The cam plate prevents opening movement of the inter locking bar 15 to the right so long as the switch is in closed position and the cam plate 42 occupies the position illustrated in Figs. 1 and 2. The door 17, therefore, cannot he opened while the switch is in closed position and is retained in closed position until the bar is moved to the right to the position indicated in dotted lines in Fig. 1.

When the switch is moved to open position, the cam plate 452 occupies the position indicated in dotted. lines in Fig. 2, wherein the QZilG-HSlOH l-i lies clear of the iimardl' v c:-;te;.ulin,g flange l2 ol the ii'itcrloching;- bar \Yhen the switch is open, the bar 1-3 may be moved to the right, in which piiish tion it extends across the pathot movement (it the cam plate 42 and prevents closing movement. of switch. At this time, the left end of the bar 4-5 is withdrawn from the path of movement of the cam plate 4:8 on the door, and opening movement of the lat.- ter is permitted.

teterring to Fig. 4;, it will be seen that, when the door is moved slightly out of closed position, the nose of the cam plate 418. extends across the path of movement of the interlocking bar and prevents releasing movement thereof. The bar, therefore, is held in interlocked position with the switch so long as the door is in open position and is in any position other than closed position. The cam plate 4.8 is provided with a stop projection 53 that engages the underside of the locking bar 45 and limits opening movement of the door.

The door 17 is provided with a latch bar that is pivoted at 55 to the door. The latch provided, at one end, with an inwardly-projecting cam plate 56 and, at the other end, with an inwardly-projecting tin- ,e'cr 5 7 that is adapted to project into a notch 58 in the interlocking bar 45 when the door is in closed position or nearly closed position. The end of the latch bar 54;, having the cam plate 56 thereon, is adapted to ex tend beneath the flange 59 of the cover 1)) and, when in the position indicated in Fig. 1. serves to retain the door in closed posi-- tion.

An operating handle (31 is secured to the latch ha 1'. and extends through a slot es in the cover] T held in the posi; tion illustrated in full lines in Fig. 1 by meant: ot a helical spring 63 hat is secured. at one end, to the latch bar. and, at the other end, to the housing by nrqins ot a riv 61;.

In order to open the door, the switch must first be moved to open position, wherethe we piste 4:2 occup es e Pe i i1.-

lustrated in dotted lines in Fig. By reason of the clearance usua ly provided in constructions, such as the switch-operating mechanism illustrated in the above-referred to co-pending application, provision is made on the locking bar to displace the extension toward open position to insure )roper operation of the switch-operating mechanism. The t'ange Z) of the locking bar 45 is therefore provided with an Ol'ltVvEilillY- turned cam. portion that is ad; )ted to engage the extreme end of the extension at and move the switch mechanism toward open position when the interlocking bar do is actuated by the latch bar After the switch has been moved to open position, the bar is turned in a clockwise direction by the handle 61 and moves the interlocking bar across ti o path or" movement of the cam plate 4-2, thus locking the switch in open position. This same movement withdraws the interlocking bar 45 from ongagement with the cam plate 4-8 and permits opening movement of the door. Clos'ng movement of the actuating bar is prevented by the cam plate 4:8 in the manner previously described.

In order to close the switch, the door 17 must first be closed. W hen the door 17 is moved to closed position, the inclined edge of the cam plate 56 on the latch bar 5% en gages the flange 59 of the housing which automatically causes the latch to be rotated in clockwise direction, thus bringing the i.nwardlyprojecting finger 5T 01" the latch bar 5 into registry with the notch on the interlocking bar.

Final closing movement moves the "finger into the notch 58 wherein it is in position to move the interlocking bar to releasing position, or to the position illustra ed in llig. 1, when the door finally reaches closed position. The free end of the latch bar 5% is drawn beneath the flange 59 of the cover 13 by the spring 53 after the door has moved to closed position. This latching movement moves the interlocking bar toward the left, thus permitting closing movement of the switch and preventing opening movement of the door.

in order to revent access to of the ho sing, the latch bar 5 1;

1 hole 66 that s with. a tl'ireaoed the slot 5?, in the door 1'? and into which a screw me so inserted while the cover 13 is open for preventing releasing movement of the door latch bar 534:. The switch-operating member a l is provided with a tli portion 66 having a series oi perforations (3? which accessible when the switch is in open position tor receiving the hasp of adlock which engages the bracket 68 and prevents closing movement of the sv'itch.

It will be seen from the foregoing that the deer doubly lo ke in dos P ition when tl e switch is in closed position, and that the s itch cannot be closed so long as the door is in open position or any position other than closed position. It is also apparent that the interlocking bar annotbe moved ept when the cover and switch are in prede in nod positions. The corn structioje simple and pos'tive in its action and relatively inexpensvc to manutacture.

Vahile I have illustrated and (.escribed but one embodiment of my invention, it will be apparent to those skilled in the art that various changes, modifications, adnitions, :uibstitutions an. omissions may be made therein without departing from the spirit and scope of my invention, as set forth in the appended claims.

I claim as my inven ion:

1. Switch mechanism comprising a housing, a movable switch member, a movable door for the housing, a movable latch for he door, an interlock member actuated by the latch for releasably retaining the door in closed position and for preventing closing movement of the switch member when inoperative to retain the door in closed position, and means actuated by the door for preventing releasing movement of the interlock member so long as the door is in other than closed position.

2. Switch mechanism comprising a housing, a movable switch member, a movable door for the housing, an interlock member for releasably retaining the door in closed position and for preventing closing movement of the switch member when inoperative to retain the door in closed position, and means u ted by the door for preventing releasi noveinent of the interlock member so-long as the door is in other than fully closed position.

" Switch mechanism comprising a' housa. ing, a movable switch member, a movable door for the housing, an interlock member slidably mounted upon the housing for releasably retaining the door in closed posi tion and for preventing closing movement of the switch member when inoperative to retain the door in closed position and means carried by the door for automatically movin the interlock member from interlockcd tion to the switch and. for locking the door in (lose-l position after the door has moved to substantially closed position.

Switch mechanism coin rising a housring, a movable switch member, a movable door tor the housing. an interior: member novable independently ot the door and wit-ch member for alternately engaging the LCil member and the door for ret- 'ning oor in closed position when the switch is in operative position and for rethe switch member in inoperative position when the door is open and means including separate means @111 the door s vitch member for preventing movement of the interlock member except when the door and switch are in predetermined positions.

5. Switch mechanism comprising a housing, a movable switch member, a movable door for the housing, an interlock member movably mounted on the housing for alternately preventing predetermined movements of the door and switch member and a latch carried by the door for operatively engaging the interlock member when the door is in closed position and for moving the interlocking member into interlocked relation to the switch during the releasing movementof the latch.

6. Switch mechanism comprising a housing, a movable switch member, a movable door for the housing, an interlock member movably mounted on the housing for alternately preventing predetermined movements 20 of the door and switch member, a latch carried by the door and means actuated by the closing movement of the door for moving the latch into operative engagement with the interlock member.

In testimony whereof, I have hereunto subscribed my name this 17th day of April 1922.

HUBERT K. KRANTZ 

